María Julia Verde-Star

Antimycobacterial Activity of Juglans regia, Juglans mollis, Carya illinoensis and Bocconia frutescens

Mycobacterium tuberculosis is a serious worldwide health threat, killing almost 2 million people per year. Alternative antimycobacterial drugs are urgently needed; studies have shown that medicinal plants traditionally used to treat respiratory diseases are a potential source of compounds to treat tuberculosis. This paper studied the antimycobacterial activity of 28 extracts from four different plant species that have been used in traditional Mexican medicine to treat tuberculosis. Bark and leaf crude extracts of Juglans regia L., Juglans mollis Engelm., Carya illinoensis (Wangenh) K. Koch and Bocconia frutescens showed in vitro anti‐M. tuberculosis activity. Hexane bark extracts from C. illinoensis, J. mollis and J. regia were the most active with a minimal inhibitory concentration (MIC) of 31, 50 and 100 µg/mL, respectively. Ethanol bark extracts from C. illinoensis and J. mollis showed activity at 100 and 125 µg/mL, respectively. Leaf extracts had the lowest activity. Methanol and hexane leaves extracts from B. frutescens had a MIC of 125 µg/mL. None of the aqueous extracts showed antimycobacterial activity. Copyright

Bioassay-Guided Isolation and Identification of Cytotoxic Compounds from Gymnosperma glutinosum Leaves

Bioassay-guided fractionation of hexane extracts of Gymnosperma glutinosum (Asteraceae) leaves, collected in North Mexico, afforded the known compounds hentriacontane (1) and (+)-13S,14R,15-trihydroxy-ent-labd-7-ene (2), as well as the new ent-labdane diterpene (−)-13S,14R,15-trihydroxy-7-oxo-ent-labd-8(9)-ene (3). In addition, D-glycero-D-galactoheptitol (4) was isolated from the methanolic extract of this plant. Their structures were established on the basis of high-field 1D- and 2D NMR methods supported by HR-MS data. The cytotoxic activity was determined by using the in vitro L5178Y-R lymphoma murine model. Hentriacontane (1) and the new ent-labdane 3 showed weak cytotoxicity, whereas the ent-labdane 2 showed significant (p < 0.05) and concentration dependent cytotoxicity (up to 78%) against L5178Y-R cells at concentrations ranging from 7.8 to 250 µg/mL.

Long-chain alkanes and ent-labdane-type diterpenes from Gymnosperma glutinosum with cytotoxic activity against the murine lymphoma L5178Y-R.

The antitumor potential of Gymnosperma glutinosum was previously reported using the in vitro and in vivo L5178Y‐R lymphoma murine model. The present study was carried out to isolate and identify the cytotoxic compounds present in the Gymnosperma glutinosum leaf hexane extract. Gymnosperma glutinosum was collected in the semi‐arid region of Escobedo, State of Nuevo León, México, but it is commonly found in northeastern Mexico; it is traditionally used as a treatment for diarrhea, ulcers and rheumatism. G. glutinosum leaves were extracted with hexane and further fractioned and subfractioned over silica gel by gradient elution with hexane, chloroform, ethyl acetate and methanol. The cytotoxicity of fractions and subfractions was assessed in vitro against L5178Y‐R lymphoma cells. Structure elucidation of the active compounds was determined by spectroscopic methods. Fractions and subfractions showed significant (p < 0.05) and concentration‐dependent 20% to 56% cytotoxicity against L5178Y‐R cells at concentrations ranging from 7.8 µg/mL to 500 µg/mL. The bioassay‐guided fractionation of the hexane extract resulted in the isolation and identification of the alkane hentriacontane and the diterpene ent‐labd‐7‐en‐13S,14R,15‐triol as the metabolites responsible for the activity. Copyright

Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase.

Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 μg/mL and 1.95 ± 0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity.

In Vitro Cytotoxic Activity of Isostichopus badionotus, a Sea Cucumber from Yucatan Peninsula Coast

The in vitro cytotoxic activity of hexane, ethyl acetate and butanol extracts of the sea-cucumber Isostichopus badionotus (Holothuroidea) was tested against normal cells (Vero), human cervical carcinoma (HeLa) and breast adenocarcinoma (MCF-7 and MDA-MB-231) ATCC cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Hexane extracts from body walls and viscera showed high cytotoxic activity against HeLa cells (IC 50 ’s = 48.5 and 42.5 µg mL -1 , respectively), while the ethyl acetate extract of body walls was considered low active (IC 50 = 98.3 μg mL -1 ). In addition, the body walls hexane extract showed a good selectivity index value of 12.0.